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INFLUENCE OF THE MIDDLE WEAK LAYER ON THE IMPACT BEHAVIOR OF LAMINATED STRUCTURES
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作者 Dongfang Wang Jialing Yang Yuxin Sun 《Acta Mechanica Solida Sinica》 SCIE EI CSCD 2013年第3期263-276,共14页
In this paper, a calculation model based on the subsection displacement theory and the large deflection analysis is developed to describe the dynamic response of isotropic laminated circular plates impacted by a soft ... In this paper, a calculation model based on the subsection displacement theory and the large deflection analysis is developed to describe the dynamic response of isotropic laminated circular plates impacted by a soft body. The model takes into account the interlaminar shear effect induced by the middle weak layer. It is proved by numerical examples that the difference between the model developed in this paper and that based on the classical laminated theory mainly depends on three factors, the elastic modulus of the glue, the radius of the circular plate and the impact force. 展开更多
关键词 laminated glass interlaminar shear stress subsection displacement theory lami-nated circular plate
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Comparison of Properties of Bastnasite and Fluorocarbonate Rare-earth Polishing Powders
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作者 何松 高勇 曾清华 《Rare Metals》 SCIE EI CAS CSCD 1998年第3期7-12,共6页
By means of DTA TG, XRD, SEM etc ., the particles configuration, crystal structure, chemical composition and other physical properties of bastnasite rare earth polishing powder and fluorocarbonate rare earth pol... By means of DTA TG, XRD, SEM etc ., the particles configuration, crystal structure, chemical composition and other physical properties of bastnasite rare earth polishing powder and fluorocarbonate rare earth polishing powder were comparatively analyzed. The mechanism of the performance differences between two kinds of polishing powders was also investigated. 展开更多
关键词 Rare earths Polishing powder Bastnasite Fluorocarbo nate
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Integrated global analysis in spider flowers illuminates features underlying the evolution and maintenance of C_(4) photosynthesis
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作者 Wei Zhao Jun Li +4 位作者 Xingchao Sun Qiwei Zheng Jing Liu Wei Hua Jun Liu 《Horticulture Research》 SCIE CSCD 2023年第8期143-157,共15页
The carbon concentrating mechanism—C_(4) photosynthesis—represents a classic example of convergent evolution,but how this important trait originated and evolved remains largely enigmatic.The spider flower Gynandrops... The carbon concentrating mechanism—C_(4) photosynthesis—represents a classic example of convergent evolution,but how this important trait originated and evolved remains largely enigmatic.The spider flower Gynandropsis gynandra is a valuable leafy vegetable crop and medicinal plant that has also been recognized as a C_(4) model species.Here we present a high-quality chromosome-scale annotated genome assembly of G.gynandra through a combination of Oxford Nanopore Technology(ONT),HiFi and Hi-C technology.The 17 super-scaffolds cover 98.66% of the estimated genome(997.61 Mb),with a contig N50 of 11.43 Mb and a scaffold N50 of 51.02 Mb.Repetitive elements occupy up to 71.91% of its genome,and over half are long terminal repeat retrotransposons(LTR-RTs)derived from recent bursts,contributing to genome size expansion.Strikingly,LTR-RT explosion also played a critical role in C_(4) evolution by altering expression features of photosynthesis-associated genes via preferential insertion in promoters.Integrated multiomics analyses of G.gynandra and the ornamental horticulture C3 relative Tarenaya hassleriana reveal that species-specific whole-genome duplication,gene family expansion,recent LTR–RT amplification,and more recent tandem duplication events have all facilitated the evolution of C_(4) photosynthesis,revealing uniqueness of C_(4) evolution in the Cleome genus.Moreover,high leaf vein density and heat stress resilience are associated with shifted gene expression patterns.The mode of C_(3)-to-C_(4) transition found here yields new insights into evolutionary convergence of a complex plant trait.The availability of this reference-grade genomic resource makes G.gynandra an ideal model system facilitating efforts toward C4-aimed crop engineering. 展开更多
关键词 UNIQUENESS nates CONVERGENT
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Altered cerebral cortical microstructure in preterm infants at term-equivalent age relative to term-born neonates
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作者 Wang Wenjun Yu Qiaowen +2 位作者 Liang Wenjia Tang Yuchun Liu Shuwei 《解剖学杂志》 CAS 2021年第S01期61-62,共2页
Preterm birth is associated with abnormal brain structure.However,the underlying microstructural properties of cerebral cortical differences in infants born very preterm(VPT,<32 GW)and moderately-late preterm(MLPT,... Preterm birth is associated with abnormal brain structure.However,the underlying microstructural properties of cerebral cortical differences in infants born very preterm(VPT,<32 GW)and moderately-late preterm(MLPT,32-37 GW)at term-equivalent age(TEA)relative to full-term(FT)neonates were rarely explored.To achieve this,we use neurite orientation dispersion and density imaging(NODDI)and the method of gray matter-based spatial statistics(GBSS).33 VPT infants,40 MLPT infants)and 69 FT neonates with no evidence of local lesions on conventional MRI adopted from dHCP database were included in this study.By extracting the core voxels of cerebral cortex from the 142 individuals in the standard space,we compared the differences between preterm groups and FT group voxel-wisely. 展开更多
关键词 CEREBRAL nates INFANTS
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Fabrication of Neutron-photon Coupling Multi-group Cross-section Library Based on Monte Carlo Method for Discrete Ordinates Transport Code
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作者 Wu Xiang Fang Peng +4 位作者 Wang Huiqiao Yang Yongwei Yang Lei Guo Yuyao Lai Hanghui 《IMP & HIRFL Annual Report》 2022年第1期204-205,共2页
Radiation shielding calculation plays a critical role in ensuring the safety of nuclear reactors.In the field of nuclear reactor shielding calculations,deterministic computing codes are commonly used due to their comp... Radiation shielding calculation plays a critical role in ensuring the safety of nuclear reactors.In the field of nuclear reactor shielding calculations,deterministic computing codes are commonly used due to their computational efficiency and capability to solve deep penetration problems.However,the accuracy of deterministic codes heavily relies on the precision of the multi-group cross section library^([1]). 展开更多
关键词 DETERMINISTIC nates COUPLING
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Nate Williams
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《计算机光盘软件与应用(COMPUTER ARTS数码艺术)》 2009年第8期56-63,共8页
Rob Carney发现,作为插画门户网站的主管,有着庞大的客户名录和另一面个性的Nate Williams是商业插画世界不可小觑的一股力量。
关键词 插画门户网站 个性化 计算机网络 nate WILLIAMS
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Radical rejuvenates the click-clip reaction
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作者 Jiong Zhou Miaomiao Yan Yuanxin Zhang 《Science China Chemistry》 2025年第3期803-805,共3页
With the widespread attention paid to the construction of functional molecular systems,chemical synthesis is increasingly pursuing the accurate and efficient combination and dissociation of molecular units to achieve ... With the widespread attention paid to the construction of functional molecular systems,chemical synthesis is increasingly pursuing the accurate and efficient combination and dissociation of molecular units to achieve specific functions[1].Carolyn R.Bertozzi,Morten Meldal,and K.Barry Sharpless,winners of the 2022 Nobel Prize in Chemistry,found that click chemistry works like LEGO bricks,using the basic block to build infinitely changing shape,which allows the molecular building block to be combined quickly and efficiently[2]. 展开更多
关键词 INFINITELY nates SYNTHESIS
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Effect of co-existing organic compounds on adsorption of perfluorinated compounds onto carbon nanotubes 被引量:6
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作者 Shubo DENG Yue BEI Xinyu LU Ziwen DU Bin WANG Yujue WANG Jun HUANG Gang YU 《Frontiers of Environmental Science & Engineering》 SCIE EI CAS CSCD 2015年第5期784-792,共9页
Co-existing organic compounds may affect the adsorption of perfluorinated compounds (PFCs) and carbon nanotubes in aquatic environments. Adsorption of perfluorooctane sulfonate (PFOS), perfluorooctane acid (PFOA... Co-existing organic compounds may affect the adsorption of perfluorinated compounds (PFCs) and carbon nanotubes in aquatic environments. Adsorption of perfluorooctane sulfonate (PFOS), perfluorooctane acid (PFOA), perfluorobutane sulfonate (PFBS), and perfluor- ohexane sulfonate (PFHxS) on the pristine multi-walled carbon nanotubes (MWCNTs-Pri), carboxyl functionalized MWCNTs (MWCTNs-COOH), and hydroxyl functiona- lized MWCNTs (MWCNTs-OH) in the presence of humic acid, 1-naphthol, phenol, and benzoic acid was studied. Adsorption kinetics of PFOS was described well by the pseudo-second-order model and the sorption equilibrium was almost reached within 24 h. The effect of co-existing organic compounds on PFOS adsorption followed the decreasing order of humic acid 〉 1-naphthol 〉 benzoic acid〉phenol. Adsorbed amounts of PFOS decreased significantly in the presence of co-existing or preloaded humic acid, and both adsorption energy and effective adsorption sites on the three MWCNTs decreased, resulting in the decrease of PFOS adsorption. With increasing pH, PFOS removal by three MWCNTs decreased in the presence of humic acid and phenol. The adsorbed amounts of different PFCs on the MWCNTs increased in the order ofPFBS 〈 PFHxS 〈 PFOA 〈 PFOS. The increase of both initial concentrations and the number of aromatic rings of co-existing organic compounds suppressed PFOS adsorption on the MWCNTs. 展开更多
关键词 perfluorinated compounds carbon nanotubes competitive adsorption humic acid perfluorooctane sulfo-nate (PFOS)
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Transition-Metal-Free Defluorosilylation of Fluoroalkenes with Silylboronates 被引量:6
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作者 Pan Gao Guoqiang Wang +3 位作者 Longlong Xi Minyan Wang Shuhua Li Zhuangzhi Shi 《Chinese Journal of Chemistry》 SCIE CAS CSCD 2019年第10期1009-1014,共6页
Silylated fluoroalkenes are important synthetic intermediates with complementary reactivity,which play a key role in the construction of natural products,pharmaceuticals,and manmade materials.Converting the normally h... Silylated fluoroalkenes are important synthetic intermediates with complementary reactivity,which play a key role in the construction of natural products,pharmaceuticals,and manmade materials.Converting the normally highly stable fiuoroalkenes into silylated fluoroalkenes by selective defluorosilylation is a challenging task.Herein,we report a simple,inexpensive and robust defluorosilylation of a variety of fluoroalkenes with silylboronates in the presence of alkoxy base to directly synthesize various silylated fluoroalkenes.The protocol features mild and safe reaction conditions that avoid a catalyst,a transition metal,a ligand,and high reaction temperature and tolerates a wide scope of fluoroalkene substrates without compromising the efficiency.Density functional theory calculations show that transient silyl anion complex undergoes an SN2,or SNv substitution,which is responsible for this base-mediated defluorosilylation. 展开更多
关键词 materials. ALKENES nates
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Visible-light mediated cross-coupling of aryl halides with sodium sulfinates via carbonyl- photoredox/nickel dual catalysis 被引量:1
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作者 Shan Jiang Zi-Tong Zhang +3 位作者 David James Young Lu-Lu Chai Qi Wu Hong-Xi Li 《Organic Chemistry Frontiers》 SCIE EI 2022年第5期1437-1444,共8页
Photoinduced nickel-catalyzed cross-coupling of arylsulfinates(ArSO_(2)^(−))with(hetero)aryl halides(Ar’–X)via visible light photoexcitation of 2-chloro-thioxanthen-9-one(Cl-TXO)has been achieved in moderate to exce... Photoinduced nickel-catalyzed cross-coupling of arylsulfinates(ArSO_(2)^(−))with(hetero)aryl halides(Ar’–X)via visible light photoexcitation of 2-chloro-thioxanthen-9-one(Cl-TXO)has been achieved in moderate to excellent yields. 展开更多
关键词 NICKEL nates coupling
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Comparison of dorsal penile nerve block alone and in combination with lidocaine–prilocaine cream in neonates undergoing circumcision: a randomized controlled study 被引量:1
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作者 Ibukunolu Olufemi Ogundele Chigbundu Collins Nwokoro +5 位作者 Tewogbade Adeoye Adedeji Arua Obasi Igwe Collins Chijioke Adumah Ademola Olusegun Talabi Aderibigbe Modupe Shonubi Oludayo Adedapo Sowande 《World Journal of Pediatric Surgery》 2022年第4期217-222,共6页
Background Suboptimal neonatal circumcision analgesia causes a significant stress response.There is continued search for more effective analgesia for neonatal circumcision.We aimed to determine whether lidocaine–pril... Background Suboptimal neonatal circumcision analgesia causes a significant stress response.There is continued search for more effective analgesia for neonatal circumcision.We aimed to determine whether lidocaine–prilocaine cream(LPC)prior to dorsal penile nerve block(DPNB)offers better analgesia than DPNB alone.Methods A prospective randomized study of 72 neonates undergoing plastibell circumcision was randomized into two groups of 36 each.Group I received DPNB alone with 4 mg/kg plain lidocaine.Group II had 1 g LPC applied to the phallus 1 hour before DPNB.Serum cortisol levels were measured 30 min preoperatively and 30 min postoperatively.Heart rate(HR)and peripheral arterial oxygen saturation(SpO2)were noted at 30 min preoperatively,after DPNB injection,after excising the prepuce,and at 30 min thereafter.The primary outcome measure was change in serum cortisol levels,while secondary outcomes were changes in HR and SpO2.Results Both groups had increased mean serum cortisol levels,decreased mean SpO2 and increased mean HR from baseline.The rise in mean serum cortisol level was significantly lower in group II(8.09±4.53µg/dL)than that in group I(11.42±7.83µg/dL)(p=0.034).Changes in SpO2 and HR were significantly less in group II than that in group I patients(p<0.05),except for HR changes at 30 min after excision of the prepuce(p=0.086).Conclusion These data suggest that neonates who received LPC prior to DPNB experienced significantly less pain from plastibell circumcision than those who had DPNB alone. 展开更多
关键词 randomized ALONE nates
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CHARACTERISTICS OF AUTHIGENIC FER-ROMANGANESE CARBONATES IN THE SANYA BAY, HAINAN ISLAND
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作者 朱而勤 王琦 张建华 《Chinese Science Bulletin》 SCIE EI CAS 1986年第11期755-760,共6页
Authigenic ferromanganese carbonates were first discovered in some shallow and hemipelagic areas by scientists abroad.These minerals have also been found on the offshore along China, especially in the South China Sea ... Authigenic ferromanganese carbonates were first discovered in some shallow and hemipelagic areas by scientists abroad.These minerals have also been found on the offshore along China, especially in the South China Sea (such as the Beibu Bay, the Sanya Bay and the continental shelf). Though the abundance of the carbonates 展开更多
关键词 shallow abundance CONTINENTAL minerals offshore SHELF HAINAN ISLAND SANDS nates manganese
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What can we learn from neonates with COVID-19?
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作者 Tian-Tian Xiao Kai Yan +1 位作者 Lai-Shuan Wang Wen-Hao Zhou 《World Journal of Pediatrics》 SCIE CAS CSCD 2020年第3期280-283,共4页
The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic.Studies on epidemiological and clinical characteristics of patients with COVI... The coronavirus disease 2019 (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has become a global pandemic.Studies on epidemiological and clinical characteristics of patients with COVID-19 have indicated that children are susceptible to SARS-CoV-2 [1-3].To date,the largest study in China reported that over 90% of 2143 children with COVID-19 were asymptomatic,or had mild or moderate illness,and that 5.8% presented critical illness [3].Although the data of neonates are limited and only six neonates with COVID-19 have been reported thus far,several important points should be addressed from these neonatal cases. 展开更多
关键词 ACUTE RESPIRATORY nates
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Outcomes of complete surgical repair versus palliative intervention in neonates with Tetralogy of Fallot
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作者 Mohammed Hamzah Hasan FOthman +3 位作者 Krystel Chedid Mohammed Alsabri Ibrahim Qattea Hany Aly 《Pediatric Investigation》 CAS CSCD 2022年第4期260-263,共4页
The ideal surgical approach when managing neonates with Tetralogy of Fallot(TOF)is still controversial.1 In 1945,subclavian artery to pulmonary artery anastomosis was created as palliation for patients with TOF.2 A de... The ideal surgical approach when managing neonates with Tetralogy of Fallot(TOF)is still controversial.1 In 1945,subclavian artery to pulmonary artery anastomosis was created as palliation for patients with TOF.2 A decade later,Lillehei et al.3 performed the first intracardiac repair for TOF with ventricular septal defect closure and right ventricular outflow obstruction relief.The surgical and perfusion techniques,as well as the postoperative care,have advanced and evolved since that time.Despite that evolution,the two concepts of surgical interventions had remained the same.There is still much debate on what is the ideal surgical approach to infants with TOF,an early primary surgical repair(EPSR)versus a two-staged surgical approach with either an initial temporary shunt for pulmonary blood flow or transcatheter cardiac palliation.The aim of this study was to determine if one strategy had lower mortality than the other and to assess the hospital length of stay and cost of charge in the study groups. 展开更多
关键词 SURGICAL nates repair
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The etiological spectrum of bowel obstruction and early postoperative outcome among neonates at a tertiary hospital in Uganda
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作者 Paul Otim Emmanuel Alex Elobu +2 位作者 Ronald Mbiine Nasser Kakembo David Komakech 《World Journal of Pediatric Surgery》 2022年第4期247-254,共8页
Background Bowel obstruction is a common surgical emergency in newborns.One-fourth of neonates with obstruction suffer postoperative complications,with high mortality,especially in low-income countries.Factors attribu... Background Bowel obstruction is a common surgical emergency in newborns.One-fourth of neonates with obstruction suffer postoperative complications,with high mortality,especially in low-income countries.Factors attributed to mortality include prematurity,late presentation and associated multiple congenital anomalies.The prevalence and the predictors of mortality in our setting have not been well studied.We aimed to describe the early postoperative outcomes and to determine the predictors of mortality among neonates with bowel obstruction.Methods We conducted a prospective cohort study during 4 months,when we recruited postoperative neonates from the pediatric surgery unit of Mulago Hospital.We collected data on demographics,clinical presentations,maternal characteristics,the surgical procedure performed,postoperative outcomes,etc.After follow-up for 2 weeks,we analyzed the data using Cox proportional hazards regression models of predictors of mortality.Results A total of 76 neonates were recruited,with a male-to-female ratio of 2.2:1.The age ranged from 1 to 26 days,a median of 3[interquartile range(IQR):2,7].About 67.1%had birth weights ranging between 2.5 kg and 3.5 kg,a mean of 2.8[standard deviation(SD)=0.64];76.3%were termed;with anorectal malformation(ARM),31.6%as the leading cause,followed by jejunoileal atresia(JIA),25%.Nearly 55.3%of neonates developed complications;53.9%with post-operative fever,15.8%had wound sepsis.The mortality rate was 44.7%(34/76)and was highest among cases of JIA,41.2%.The predictors of mortality included prematurity,fever at admission,breastfeeding status,and mother’s parity as well as the cadre of healthcare providers(p<0.005).Conclusions ARM is the predominant cause of bowel obstruction among neonates,followed by JIA.The morbidity and mortality due to bowel obstruction among neonates are unacceptably high.The major predictors of mortality were prematurity,fever at admission,and the cadre of the healthcare providers. 展开更多
关键词 POSTOPERATIVE MOTHER nates
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Natee Utarit 延续画作的灵魂
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作者 尹宝燕 王媛媛 《明日风尚》 2011年第1期176-177,共2页
科技教会了我们如何以客观、精确来观察万物。在手中没有手机,耳边没有听筒的年代,那种通过想像力来认知世界的方式,被视为一种漠视文明的错误态度。在急速的进步中,促使我们以理智为尺度去理解一切,因此全面捕捉此情此景的摄影技术,取... 科技教会了我们如何以客观、精确来观察万物。在手中没有手机,耳边没有听筒的年代,那种通过想像力来认知世界的方式,被视为一种漠视文明的错误态度。在急速的进步中,促使我们以理智为尺度去理解一切,因此全面捕捉此情此景的摄影技术,取代了画笔成为记载历史和生活的工具。在客观态度的影响下,艺术的价值不仅在于作品所蕴藏的涵义,而是在于它在拍卖会上在哪个价位被判处流放。冷冰冰的外在因素,逐渐侵蚀着艺术作为灵性载体的本质。 展开更多
关键词 摄影技术 natee Utarit 卡拉瓦乔 认知世界 西方艺术家 美国画家 当代艺术家 表现派
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基于改进暗通道先验和ADMM优化的图像盲复原
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作者 赵小强 王涛 宋昭漾 《传感技术学报》 北大核心 2025年第8期1406-1414,共9页
针对运动退化图像中存在较大噪声时,暗通道先验无法准确估计点扩散函数和在最大后验框架下采用梯度先验约束难以求得最优解的问题,提出一种基于改进暗通道先验和ADMM优化的运动退化图像盲复原算法。首先,根据分数阶具备非线性保留低频... 针对运动退化图像中存在较大噪声时,暗通道先验无法准确估计点扩散函数和在最大后验框架下采用梯度先验约束难以求得最优解的问题,提出一种基于改进暗通道先验和ADMM优化的运动退化图像盲复原算法。首先,根据分数阶具备非线性保留低频成分和抑制噪声的特点,使其对暗通道先验进行改进;然后通过改进的暗通道先验构造出点扩散函数估算模型并采用半二次方分裂方法解决其非凸问题;在对点扩散函数进行复原时,采用由粗到细的多尺度交替迭代优化框架,使得迭代出的最大尺度点扩散函数更加精确;最后建立导数空间总变分模型,利用交替方向乘子法(ADMM)对其进行优化,从而达到在导数空间总变分模型之下可以收敛到最优解、复原出更多图像细节的目的。实验结果表明:所提算法可以有效降低图像中的噪声、伪影和振铃现象,使得复原出的图像更加清晰、具有更多的图像细节。 展开更多
关键词 图像处理 运动退化图像盲复原 暗通道先验 点扩散函数 多尺度 交替方向乘子法
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考虑站点转乘的公交接驳地铁站点群线路优化
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作者 王连震 杜翼飞 +2 位作者 刘克毅 周铭 薛淑祺 《北京交通大学学报》 北大核心 2025年第4期41-51,共11页
为促进公交与地铁之间的有效接驳,针对地铁站点群周边接驳公交线路的客流时空分布及换乘效率进行协同优化研究.构建考虑系统总成本最小化和线网换乘需求最大化的多目标优化模型,并增设换乘时间成本和换乘次数的惩罚机制,对涉及两次或更... 为促进公交与地铁之间的有效接驳,针对地铁站点群周边接驳公交线路的客流时空分布及换乘效率进行协同优化研究.构建考虑系统总成本最小化和线网换乘需求最大化的多目标优化模型,并增设换乘时间成本和换乘次数的惩罚机制,对涉及两次或更多换乘的情况加以约束,促使系统在设计时尽可能减少不必要的换乘.引入自适应精英保留策略和惯性系数动态调整策略,设计并采用遗传粒子群混合算法来求解模型.研究结果表明:在接驳公交服务能力方面,相较于原有公交线网,优化后的公交载客量提升约23%;在经济性维度,乘客人均出行成本降低约9%;在算法性能上,所设计的混合优化算法较传统遗传算法运行速度提升15.4%.优化模型在换乘吸引力、人均出行成本等多个关键指标上均优于既有公交线路,验证了模型在提升接驳公交网络运营效率和服务质量方面的有效性,可以为城市公共交通系统的精细化管理和智能化升级提供参考. 展开更多
关键词 城市交通 地铁站点群 接驳公交线路 多目标协同优化 遗传粒子群混合算法
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无线传感网络入侵干扰节点定位方法的优化设计 被引量:1
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作者 贾仁祥 单鸿涛 《传感技术学报》 北大核心 2025年第8期1511-1518,共8页
为了维护无线传感网络的运行稳定性,设计一种无线传感网络入侵干扰定位优化方法。通过粒子群算法的方式,完成对无线传感网络入侵样本的取样,不再标记所有节点,实现对无线传感网络入侵对象的简洁标记。放弃入侵前阈值定义入侵等级的传统... 为了维护无线传感网络的运行稳定性,设计一种无线传感网络入侵干扰定位优化方法。通过粒子群算法的方式,完成对无线传感网络入侵样本的取样,不再标记所有节点,实现对无线传感网络入侵对象的简洁标记。放弃入侵前阈值定义入侵等级的传统思路,查询关键节点对象,并针对其定义攻击性判定Hash函数,联合相关攻击项,判定已标记对象入侵攻击等级。在无线传感网络中实施入侵信息的拟合处理,根据无线传感网络划分条件,定位入侵攻击项,完成无线传感网络入侵干扰节点定位。仿真结果表明,所提技术定位偏差在0.5~0.1之间,字段检测长度与真实长度的数值比保持在99%以上,检测时间低于30 s。符合检测无线传感网络攻击性信息的实际应用需求。 展开更多
关键词 无线传感网络 入侵干扰节点定位 粒子群算法 边界坐标 HASH函数 信息拟合 优化设计
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基于化学计量反应的FTIR法快速检测食用油中的过氧化值
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作者 叶沁 严海萍 +2 位作者 傅晓勇 刘睿杰 孟祥河 《中国粮油学报》 北大核心 2025年第4期170-175,共6页
为了开发食用油过氧化值(PV)的快速测定方法,本研究基于对苯磺酰异氰酸酯(TSI)与食用油中氢过氧化物反应,及其在2235cm^(-1)处的异氰酸酯(-N=C=O)反对称吸收峰变化的原理,通过透射傅里叶中红外光谱法构建过氧化值模型。研究校正了水分... 为了开发食用油过氧化值(PV)的快速测定方法,本研究基于对苯磺酰异氰酸酯(TSI)与食用油中氢过氧化物反应,及其在2235cm^(-1)处的异氰酸酯(-N=C=O)反对称吸收峰变化的原理,通过透射傅里叶中红外光谱法构建过氧化值模型。研究校正了水分副反应引起的误差,分析了模型的准确度,并与化学滴定法进行了比较。结果表明:其模型验证集FTIR法的重复性(SDr=0.0037g/100g)和优于滴定法(SDr=0.0046g/100g);不同种类食用油实际样品的外部验证结果表明,FTIR法的重复性(SDr=0.0037g/100g)要明显好于滴定法(SDr=0.0079g/100g),预测值和标准滴定值高度相关(R^(2)=0.9966),回归系数1.004,截距0.001,标准差为0.0065,显示所建方法与国标法测定过氧化值结果高度一致。 展开更多
关键词 傅里叶红外光谱 食用油 过氧化值 对苯磺酰异氰酸酯 检测
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